I am serious! ! Can cousins fall in love? Can I get married? Don't say it's ok to play, I want my friends to talk about it! ! !

Cousins are close relatives by blood. If you are in love, you will eventually get married, which will affect the growth of future generations, unless you don't want children. Cousin marriage is a relatively common consanguineous marriage.

Most countries do not encourage consanguineous marriage, or even prohibit it.

When close relatives get married, the mortality rate of offspring is high, and dementia, deformed children and genetic diseases often appear. This is because couples who get married by close relatives get more of the same genes from their ancestors, which makes it easy for recessive harmful genes that are not conducive to survival to meet in their offspring (that is, homozygous), so it is easy to give birth to children with poor quality.

According to the estimation of the World Health Organization, everyone in the population carries about 5-6 recessive genetic diseases. In random marriage (non-consanguineous marriage), it is not easy to form homozygotes (patients) with recessive pathogenic genes because the husband and wife are not related by blood, have few identical genes and carry different recessive pathogenic genes. However, when close relatives get married, it is very likely that both husband and wife carry the same recessive pathogenic gene, so it is easy to meet in offspring, which will increase the incidence of genetic diseases in offspring.

The incidence of inbreeding offspring is several times higher than that of non-inbreeding offspring. In addition, the incidence of polygenic genetic diseases is high, such as hypertension, schizophrenia, congenital heart disease, anencephaly, epilepsy and so on. The mortality rate of children born of consanguineous marriage is also significantly higher than that of children born of non-consanguineous marriage. To this end, many countries have passed laws prohibiting consanguineous marriage. Article 6 of the Marriage Law of China stipulates:

"Direct blood relatives and collateral blood relatives within three generations are forbidden to get married."

Lineal consanguinity refers to the relationship between parents and children, grandparents and grandchildren, and grandparents and grandchildren.

Collateral blood relatives within three generations include compatriots, uncles (aunts) nephews (female), uncles (aunts) nephews (female) and cousins.

According to the survey, the rate of consanguineous marriage is about 0.7% in cities, 1.2% in rural areas, and some are as high as 2.8%. In some mountainous areas, rural areas and islands, due to underdeveloped transportation, the proportion of close relatives is high, so there are more genetic diseases. Therefore, forbidding consanguineous marriage is an effective measure to reduce or even eliminate the incidence of recessive genetic diseases and improve the quality of the population, which is one of the main contents of eugenics.